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Rails has_and_belongs_to_many migration
I have two models restaurant and user that I want to perform a has_and_belongs_to_many relationship.
4 Answers
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RSA Public Key format
...ers from ---- BEGIN SSH2 PUBLIC KEY ---- to -----BEGIN RSA PUBLIC KEY----- and expect that it will be sufficient to convert from one format to another (which is what you've done in your example).
This article has a good explanation about both formats.
What you get in an RSA PUBLIC KEY is closer to...
Rails “validates_uniqueness_of” Case Sensitivity
...validates the uniqueness of 'foo' by asking the DB if that name exists yet and the DB says the name doesn't exist yet.
Process B does the same thing and gets the same response
Process A submits the insert statement for the new record and succeeds
If you have a database constraint requiring uniquenes...
LESS CSS nesting classes
I'm using LESS to improve my CSS and am trying to nest a class within a class. There's a fairly complicated hierarchy but for some reason my nesting doesn't work.
I have this:
...
Why does an overridden function in the derived class hide other overloads of the base class?
...ding happens, people who respond either say that this called "name hiding" and explain how it works (which you probably already know), or explain how to override it (which you never asked about), but nobody seems to care to address the actual "why" question.
The decision, the rationale behind the n...
C# version of java's synchronized keyword?
...: only apply thread-safety when you know you actually are going to use it (and test it).
For the method-level stuff, there is [MethodImpl]:
[MethodImpl(MethodImplOptions.Synchronized)]
public void SomeMethod() {/* code */}
This can also be used on accessors (properties and events):
private int ...
Regular expression for letters, numbers and - _
...iteral .
References
regular-expressions.info/Anchors, Character Classes and Repetition
In PHP
Here's a snippet to show how you can use this pattern:
<?php
$arr = array(
'screen123.css',
'screen-new-file.css',
'screen_new.js',
'screen new file.css'
);
foreach ($arr as $s) {
if...
How to use custom packages
I'm trying to create and use a custom package in Go. It's probably something very obvious but I cannot find much information about this. Basically, I have these two files in the same folder:
...
How can I calculate the number of lines changed between two commits in git?
...rather than specifying commit ranges, just select commits since last week) and --no-merges (merge commits don't actually introduce changes), as well as the pretty output options (--pretty=oneline, short, medium, full...).
Here's a one-liner to get total changes instead of per-commit changes from gi...
Concatenating multiple text files into a single file in Bash
What is the quickest and most pragmatic way to combine all *.txt file in a directory into one large text file?
12 Answers
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